Fault detection device
AssigneeDenso Corporation
InventorShingo Takinai
Life of this patent
Estimating the term…
Abstract
A fault detection device has a pair of power supply lines connected to a high voltage battery via power supply relays. Capacitors and inverters for driving a motor are disposed between the power supply lines. A controller in the fault detection device controls the inverters to discharge the capacitors at different times after the power supply from the battery to motor is stopped by switching OFF the power relays. The controller then determines whether the capacitor voltage has dropped after each capacitor is discharged. Based on the determination result of the voltage drop in each of the capacitors, the controller can determine whether the power supply relays or the capacitors are malfunctioning.
Claims14
A fault detection device for detecting faults in a motor driving circuit that includes:
- a pair of power lines, with one of the power lines connected to a positive side of a power source and having at least one power supply relay disposed thereon and another of the power lines connected to a negative side of the power source and having at least one power supply relay disposed thereon;
- at least one capacitor connected to each of the power lines;
- and a plurality of motor drivers connected in parallel with each other, each of the plurality of motor drivers connected to each of the power lines and configured to control the discharge of the at least one capacitor, the fault detection device comprising:
- a discharge controller configured to
- instruct each of the plurality of motor drivers at different times to perform a discharge control for discharging the at least one capacitor after performing an interruption process to turn the at least one power supply relay from ON to OFF, and
- determine for each of the plurality of motor drivers whether the discharge control of the at least one capacitor causes a drop of a capacitor voltage by measuring the capacitor voltage of the at least one capacitor, after each of the plurality of motor drivers performs the discharge control of the at least one capacitor, the capacitor voltage being a voltage between two terminals of a capacitor;
- and
- an abnormality determiner configured to detect an ON fault of the at least one power supply relay and to distinguish the ON fault from an abnormality in the discharge control of the at least one capacitor by at least one of the plurality of motor drivers based on the drop of the capacitor voltage.
A fault detection device for detecting faults in a motor driving circuit that includes a pair of power lines, with one of the power lines connected to a positive side of a power source and having at least one power supply relay disposed thereon and another of the power lines connected to a negative side of the power source and having at least one power supply relay disposed thereon;
- at least one capacitor connected to each of the power lines;
- and a plurality of motor drivers connected in parallel with each other, each of the plurality of motor drivers connected to each of the power lines and configured to control the discharge of the at least one capacitor, the fault detection device comprising:
- a controller configured to
- instruct each of the plurality of motor drivers at different times to perform a discharge control for discharging the at least one capacitor after performing an interruption process to turn the at least one power supply relay from ON to OFF,
- determine for each of the plurality of motor drivers whether the discharge control of the at least one capacitor causes a drop of a capacitor voltage by measuring the capacitor voltage of the at least one capacitor, after each of the plurality of motor drivers performs the discharge control of the at least one capacitor,
- detect an ON fault of the at least one power supply relay and to distinguish the ON fault from an abnormality in the discharge control of the at least one capacitor by at least one of the plurality of motor drivers based on the drop of the capacitor voltage.
Dependencies are inferred from the claim text.